An automatic method for determining specimen absorbed energy in drop weight impact tests is presented. The method has distinct time and materials savings advantages for the ASTM Test for Dynamic Tear Energy of Metallic Materials (E 604-77) and is also applicable for use with pendulum impact machines. The times for interruption of a precise light beam, by a flag of known width, are measured at impact and after completion of the specimen fracture. A microprocessor device computes the hammer velocities and the change in kinetic energy, which is equated to that absorbed by the specimen. The three computed values are instantaneously presented on digital displays. Operational features of the device, computational methods, accuracy and limitations of the method, and comparative results with two other methods are presented.